WO2007090445A1

WO2007090445A1 - Construction panel

Info

Publication number: WO2007090445A1
Application number: PCT/EP2006/010459
Authority: WO
Inventors: Thomas Koslowski
Original assignee: Knauf Perlite Gmbh
Priority date: 2006-02-09
Filing date: 2006-10-31
Publication date: 2007-08-16
Also published as: JP2009526147A; EP1981826B2; EP1981826A1; UA95623C2; DE102006005899A1; CN101336212A; DE102006005899B4; CA2637451C; US20090038248A1; MX2008010036A; US8091304B2; CA2637451A1; RU2008132467A; EP1981826B1; EP1981826B9; ATE542782T1; RU2434823C2; PL1981826T5; JP5290771B2; PL1981826T3

Abstract

The invention relates to a construction panel, in particular for use in dry construction.

Description

Building board

Description

The invention relates to a building board, in particular for use in dry construction.

Such building boards are also known in particular in the form of so-called cement building boards. Cement building boards are created using a cement-based binder.

To improve the insulating properties and to reduce the weight of such building boards, it is known to add a porous bulk material, in particular in the form of expanded clay, expanded slate, expanded glass or pumice, to the binder mixture.

One disadvantage is the relatively high density of these components, which is usually in the range from 350 to 700 kg / m ³ . As a result, the density or the weight of the building board can only be reduced to a limited extent. Also the insulation properties of building boards that are under With the aid of the aforementioned, porous bulk materials are created, are in need of improvement.

However, the disadvantage of using the aforementioned bulk goods is in particular that they are only available to a limited extent internationally, which is why they usually first have to be transported to the site of the construction panel production with great logistical effort.

Expanded perlite would be an excellent alternative to the aforementioned, porous bulk goods, as this material has an extremely low density (dry bulk density (bulk weight) only about 70 kg / m ³ ) and the insulating properties of a building board made using expanded perlite are therefore sustainably improved could. However, it is also particularly advantageous that pearlite has an expansion factor of approximately 10 to 15, that is to say it expands by the aforementioned factor when raw perlite is expanded to form expanded perlite. Due to its small footprint, raw pearl can therefore be transported to the place of use with little logistical effort and only expanded there.

There has therefore been no lack of attempts in practice to use expanded perlite for use in building boards. Such a use of perlite has so far failed in particular because of the high absorbency of expanded perlite, which led to the expanded perlite soaking up water or other moist constituents of the moist binder mixture. The residual moisture of these building boards was often well over 50%. This caused significant problems, especially with drying (which was common sufficient drying cannot be achieved at all; Otherwise, drying to the desired residual moisture in reasonable periods of time could only be achieved with the aid of drying systems, which was associated with considerable costs).

The invention is based on the object of providing a building board which is produced using expanded perlite, the aforementioned problems not occurring.

This problem is solved by a building board with the following features:

- A matrix of a set, inorganic binder;

- grains of expanded perlite are embedded in the binder matrix;

- The grains of expanded perlite have a water repellent coating.

According to a preferred development of this building board, it also has the following features:

- An inert filler is embedded in the binder matrix;

- The inert filler has a dry bulk density which is higher than the dry bulk density of the hydrophobized expanded perlite. A central idea of the invention is to apply a water repellent directly to the expanded perlite. Penetration of water, in particular mixing water of the binder mixture, or other liquid into the grains of expanded perlite is effectively prevented.

The mass hydrophobization of binder mixtures is known from the prior art, for example from EP 0 829 459 B1, in order to thereby reduce the penetration of moisture from the binder mixture into absorbent components of the binder mixture. However, penetration of moisture, in particular of mixing water for the binder mixture, into expanded perlite cannot be prevented to a sufficient extent by a mass hydrophobization.

The residual moisture of the building board according to the application can be, for example, between 10 and 20% by mass, based on the total weight of the building board, without further drying of the board.

The problem is known from experiments with building boards produced using expanded perlite that the dry bulk density of the building board is sometimes reduced by the expanded perlite to such an extent that the building board is "too light" for numerous practical applications These building panels, which are too light, are also susceptible to wind separation on the outside of the building. Furthermore, it was found in the case of corresponding building boards that when the binding agent set, there was sometimes considerable shrinkage and resulting shrinkage cracks in the building board.

To solve the aforementioned problems, another central idea of the invention is to provide a component in the form of an inert filler in the binder mixture in addition to the component of the expanded perlite grains.

On the one hand, this inert filler, which has a dry bulk density that is higher than the dry bulk density of the hydrophobized expanded perlite, allows the average density or the (surface) weight of the building board to be individually adjusted or increased. If, for example, a relatively high proportion of expanded perlite is used (which significantly reduces the density of the building board and improves its insulating properties), a relatively higher proportion of inert filler can also be used at the same time, whereby the density of the building board can be increased to a desired value . Correspondingly, depending on the desired density or the desired (surface) weight of the building board, as well as depending on the desired insulating properties of the building board and the resulting proportion of expanded perlite in the building board, the amount of inert filler in the building board varies and can be set.

On the other hand, however, the filler can in particular also prevent excessive shrinkage when the binding agent sets will. This is due in particular to the fact that the filler is not subject to shrinkage due to its inert properties. According to the invention, it was found that the inert filler is particularly resistant to shrinkage when the proportion of pores below 0.1 μm in the inert filler is below 3% (based on the total pore volume of the inert filler).

According to the invention, it was also found that the strength of a building board according to the application can be increased by adding more inert filler. This is evidently due to the shrinkage properties of the binder mixture, which are greatly improved with the use of inert filler. If the strength of the building board decreases with an increased proportion of expanded perlite, more inert filler can be added in order to increase the strength again.

The building board according to the application can in principle be created on the basis of any inorganic binder. A binder in the form of cement, particularly preferably Portland cement, for example CEM I 32.5 R, CEM I 42.5 R or CEM I 52.5 R, can preferably be used.

The set binding agent forms a matrix in which one or more components of the binding agent mixture, from which the building board according to the application is made, are embedded.

One of the other components are the grains of expanded perlite. These grains of expanded perlite can, for example, be a Have grain size in the range from greater than 0 mm to 6 mm. The expanded perlite is particularly preferably present in a grain size in the range from 0.1 mm to 3 mm. The grains of expanded perlite can, for example, also have a grain size in the range from 0.1 mm to 6 mm, from 0.5 mm to 6 mm, from 1 mm to 6 mm, from 0.5 mm to 3 mm, or from 1 mm to 3 mm are present.

The largest grains of expanded perlite preferably have a grain size that is less than a third of the thickness of the building board.

The dry bulk density (bulk density) of the expanded perlite (without applied hydrophobization) used for the prehydrophobization according to the invention can be, for example, in the range from 40 to 100 kg / m ³ , for example 60 to 80 kg / m ³ . The dry bulk density of the hydrophobized perlite can, for example, be in the range from 50 to 150 kg / m ³ , that is to say for example also in the range from 70 to 100 kg / m ³ .

According to the invention, a hydrophobization is applied to the grains of expanded perlite. For example, a hydrophobization in the form of wax, silicone, preferably for example in the form of silicone oil, or in the form of sodium oleate can be applied to the grains of expanded perlite. The hydrophobization can preferably be applied in liquid form, for example in the form of an aqueous emulsion, for example in the form of a liquid sodium oleate or in the form of an aqueous emulsion of a polydimethylsiloxane. The grains of expanded perlite, which have already been pre-hydrophobed, are then incorporated into the binder mixture.

Perlite grains pre-hydrophobicized according to the invention can in particular be characterized in that they are present in the binder matrix with a hydrophobicized "outer skin", while at the same time no components of the binder mixture, in particular no liquid components, have penetrated the interior of the grains.

Instead of grains made of expanded perlite, grains made of expanded vermiculite or foam glass can be used in an equivalent manner, cumulatively or alternatively. For grains made of expanded vermiculite and foam glass, the statements made here on expanded perlite apply accordingly.

In addition, it can be provided that the binder mixture is additionally mass-hydrophobized. The binder mixture can be hydrophobized, for example, by wax, silicone or by a sodium oleate. Due to the mass hydrophobization of the binding agent mixture, the set binding agent mixture and thus the building board are effectively protected against the ingress of moisture.

The binder mixture from which the building board according to the application is made contains inert filler as a further component. In principle, any inert filler can be used whose dry bulk density is higher than the dry bulk density of the hydrophobized expanded perlite. An inert filler in the form of Rock powder, particularly preferably used in the form of limestone powder. In general, one or more of the following inert fillers, which are preferably used in the form of flour or in fine-grained form, can be used: limestone powder, sand, greywacke, basalt, dolomite, volcanic rock, slate (clay slate) or recycling material from the production of the applications according to the application Building board.

According to the application, an "inert" filler is provided in order not to adversely affect the setting behavior of the binder or the binder mixture or to be able to even improve it. Thus, as shown above, the inert filler improves the shrinkage properties of the binder mixture.

What is understood by an "inert" filler is well known to those skilled in the field of binders, so that a further definition can be dispensed with here. In particular, it is known that a filler has no hydraulic or latent hydraulic properties or that the filler does not show any significant chemical reactions in the binder mixture.

The dry bulk density (bulk density) of the inert filler can, for example, be in the range from 150 to 1500 kg / m ³ , so for example also in the range from 300 to 1000 kg / m ³ or from 350 to 800 kg / m ³ .

In addition to binders, hydrophobized expanded perlite and optionally inert filler, the binder mixture or the building board according to the application created therefrom contain one or more further components. For example, the binder mixture can contain additional proportions of a pozzolanic or latently hydraulic substance, such as, for example, fly ash.

According to a preferred embodiment, the building board has cover layers on at least one, preferably on both main surfaces (that is to say the two large surfaces of the building board). Such a cover layer can consist, for example, of a set inorganic binder, preferably a binder slip. Reinforcement, in particular in the form of a fiber mat, can preferably be embedded in this binding agent.

These cover layers cover the "core" of the building board, which is designed as described above, from the outside. The binder of the cover layers preferably consists of the same binder as the "core" of the building board, that is, preferably of a Portland cement.

The fiber mat is preferably made from glass fibers (coatings) protected from alkali etching or from alkali-resistant glass fibers. The fiber mat can in particular also be provided alone in the edge or edge areas of the building board in order to strengthen the edges.

The outer sides of the building board, in particular, can be designed advantageously through the cover layers. The building board can be given a visually appealing, smooth surface by means of a cover layer made from a binder slip. The binder of the outer layers can be mass-hydrophobized, for example by wax, silicone or by a sodium oleate. Due to the mass hydrophobization of the cover layers, the building board is particularly effectively protected against the ingress of moisture.

The components of the building board according to the application can, for example, be in the range of the following mass proportions (based on the total mass of the building board):

- Binder in the range from 10 to 40% by mass, so for example also in the range from 15 to 35% by mass or in the range from 20 to 30% by mass;

- Hydrophobic expanded perlite in the range from 3 to 30% by mass, thus for example also in the range from 5 to 20 or in the range from 5 to 15% by mass;

- optionally water (residual moisture) in the range from 0 to 20% by mass, for example also in the range from 5 to 20% by mass or in the range from 10 to 15% by mass;

- if necessary, further components in the range from 0 to 70% by mass, for example also in the range from 20 to 60% by mass or in the range from 30 to 60% by mass.

In the case of a building board according to the application produced with the additional use of inert filler, the components can, for example, be in the range of the following mass fractions (based on the total mass of the Building board):

- Inert filler in the range from 10 to 70% by mass, thus for example also in the range from 20 to 60% by mass, in the range from 30 to 60% by mass or in the range from 40 to 60% by mass;

optionally further components in the range from 0 to 20% by mass, for example also in the range from 2 to 15% by mass.

While building boards of the generic type could previously be produced in a density range of approximately 1,000 to 1,200 kg / m ³ , the building board according to the application can be made up, for example, in a density range of 300 to 1,200 kg / m ³ . The building board preferably has a density in the range from 350 to 1,000 kg / m ³ , that is to say for example also in the range from 400 to 900 kg / m ³ or from 500 to 800 kg / m ³ . The above and other density and weight information in this application are to be understood as information based on the dry bulk density of the product.

In the case of building boards, the weight per unit area often also plays an important role. With a thickness of a building board according to the application in the range of 10 to 15 mm, for example with a thickness of 12.5 mm, for example, building board according to the application can be made up with a weight per area in the range of 4 to 15 kg / m ² , for example also in a range from 5 to 13 kg / m ² , from 5 to 12 kg / m ² or from 6 to 10 kg / m ² .

An exemplary composition of a building board according to the application is as follows:

- Portland cement: 24.1% by mass

Expanded hydrophobized perlite (hydrophobization in the form of silicone oil; grain size perlite 0.1 - 3 mm): 9.8% by mass

- Limestone powder: 49.5% by mass

- Residual moisture: 16.6% by mass.

An exemplary composition of a cover layer to be applied to the building board according to the application is, for example, as follows:

- Portland cement: 20.0 mass%

- Limestone powder: 60.0% by mass

- Glass fiber mat: 7.7% by mass

- Residual moisture: 12.3% by mass. An exemplary composition of a building board according to the application, which is provided with a cover layer on each of its two main surfaces, is, for example, as follows:

- Portland cement: 23.3 mass%

- Expanded hydrophobized perlite (hydrophobization in the form of silicone oil; grain size perlite 0.1 - 3 mm): 10.0% by mass

- Limestone powder: 52.4% by mass

- Glass fiber mat: 1.3 mass%

- Residual moisture: 13% by mass.

The building board according to the application can, for example, have a thickness in the range from 10 to 15 mm, for example a thickness of 12.5 mm.

The cover layers can, for example, each have a thickness in the range from 0.5 to 3 mm, for example also a thickness of 1 mm. A plate that is 12.5 mm thick can therefore have, for example, a "core" with a thickness of 10.5 mm, which has a cover layer with a thickness of 1 mm each on its two main surfaces.

The building board according to the application is particularly suitable for use in dry construction, for example as a wall or floor board, in particular, for example, also as a plaster base board.

All of the aforementioned features of the building board according to the application can be combined with one another individually or in any combination will.

An embodiment of a building board according to the application is explained in more detail with reference to the following description of the figures.

It shows, very schematically,

FIG. 1 shows a detail from a cross section through a building board according to the application in a side sectional view.

In Figure 1, a section through a building board 1 is shown, which is composed of a core 3, on one of the main surfaces 9 (here the upper) and the second main surface 11 (here the lower) each have a cover layer 5 (top) and a Cover layer 7 (below) is applied.

The core 3 of the building board 1 is made from a binder mixture composed of Portland cement, expanded perlite hydrophobized with silicone oil, and limestone powder. Furthermore, the core 3 of the building board 1 is mass-hydrophobized by means of sodium oleate.

In the core 3 of the building board 1, the set Portland cement forms a matrix 13 in which the grains of hydrophobized expanded perlite 15 and the limestone powder 17 are embedded as an inert filler.

The core 3 of the building board 1 has a thickness of 10.5 mm here.

As shown in Figure 1, the grains of hydrophobized expanded perlite 15 each have an outer skin 16 made of hydrophobing agent, which prevents the penetration of liquid into the grains of perlite 15.

Along its two main surfaces 9 and 11, the building board 1 each has a cover layer 5, 7 which each completely cover the core 3 to the outside.

The cover layers 5, 7 are each 1 mm thick and are made from Portland cement, in which a glass fiber mat 19, 21 is embedded in each case. The cover layers 5, 7 are mass-hydrophobicized by a silicone oil emulsion.

In the exemplary embodiment, the “boundaries” 23, 25 between the cover layers 5, 7 and the core 3 are indicated as a sharp dividing line for the sake of clarity cannot always be made out.

Claims

Building board patent claims

1.Building board, especially for use in drywall construction, with the following features:

1.1 a matrix (13) made of a set, inorganic binder;

1.2 grains of expanded perlite (15) are embedded in the binder matrix (13);

1.3 a water repellent (16) is applied to the grains of expanded perlite (15).

2. Building board according to claim 1 with the further features:

1.4 an inert filler (17) is embedded in the binder matrix (13);

1.5 the inert filler (17) has a dry bulk density which is higher than the dry bulk density of the hydrophobized expanded perlite (15).

3. Building board according to claim 1 with a binder in the form of Portland cement.

4. Building board according to claim 1, wherein the grains of expanded perlite (15) have a grain size in the range from greater than 0 mm to 6 mm.

5. Building board according to claim 1, wherein the grains of expanded perlite (15) have a grain size in the range of 0.1 mm to 3 mm.

6. Building board according to claim 1, in which a hydrophobing (16) in the form of silicone, in particular in the form of silicone oil, is applied to the grains of expanded perlite (15).

7. Building board according to claim 2 with an inert filler (17) in the form of rock flour, in particular in the form of limestone powder.

8. Building board according to claim 1, the components of which are in the range of the following mass fractions:

8.1 binders in the range from 10 to 40% by mass;

8.2 hydrophobic expanded perlite (15) in the range from 3 to 30% by mass;

8.3 water (residual moisture) in the range from 0 to 20% by mass;

8.4 further components in the range from 0 to 70% by mass.

9. Building board according to claim 2, the components of which are in the range of the following mass fractions:

9.1 binders in the range from 10 to 40% by mass;

9.2 hydrophobic expanded perlite (15) in the range from 3 to 30% by mass;

9.3 inert filler (17) in the range from 10 to 70% by mass;

9.4 Water (residual moisture) in the range from 0 to 20% by mass;

9.5 further components in the range from 0 to 20% by mass.

10. Building board according to claim 2 with a dry bulk density of the hydrophobic expanded perlite (15) in the range from 50 to 150 kg / m ³ and a dry bulk density of the inert filler (17) in the range from 150 to 1500 kg / m ³ .